Firearm projectiles are designed to have a variety of properties when they impact a target or other object after being fired from a firearm. Some firearm projectiles are designed to be penetrators that are very strong and are intended to pierce the impacted object while at least substantially retaining the projectile's shape. Some firearm projectiles are designed to be ductile so that the projectile deforms, typically by expanding in width, when it impacts and/or penetrates the impacted object. Other firearm projectiles are designed to break into very small particles when the projectiles impact a hard object. These latter firearm projectiles may be referred to as frangible firearm projectiles.
Frangible firearm projectiles often are used in practice ranges and other situations where ricocheting projectiles, or larger fragments thereof, are undesirable. An example of an existing frangible firearm bullet is a Sinterfire™ bullet, such as is disclosed in U.S. Pat. Nos. 6,090,178 and 6,263,798, the disclosures of which are hereby incorporated by reference. Sinterfire™ is a trademark of Sinterfire, Inc. of Kersey, Pa. USA. Sinterfire™ firearm projectiles have proven to be effective frangible firearm projectiles, but the copper and tin powders used to form the projectiles are comparatively more expensive than many other powders that are used in firearm projectiles. Thus, there is a need for an effective frangible firearm projectile alternative to Sinterfire™ projectiles.